Linear Technology Corporation

Teradyne, Inc.

Hewlett-Packard Company

Agilent Technologies, Inc.

Blue Line Engineering Company

Blue Line Engineering

Steven Douglas Roach

Gregory H Ames

Hamid Kharrati

Joseph Sascha Willis

Philip N Zercher

Jill Marie Pamperin

A transconductor converts voltage on an inductive sensor to a proportional current using two 'coupling' capacitors. Responsive to movement of an electrically conductive target from the null position a resonant current is formed between the two sensor coils. A single differential transistor pair switched by periodic drive signals commutes the net alternating current at the single input to direct current.

Inductive sensor with demodulator

An apparatus includes a first oscilloscope having multiple channels, and a second oscilloscope having multiple channels. The first oscilloscope is configured to operate as a master or as a slave. The first oscilloscope operates as the master by using a first trigger signal and a first clock signal that are native to the first oscilloscope, and the first oscilloscope operates as the slave by using a second trigger signal and a second clock signal that are native to the second oscilloscope. The second oscilloscope is configured to operate as the master or as the slave. The second oscilloscope operates as the master by using the second trigger signal and the second clock signal, and the second oscilloscope operates as the slave by using the first trigger signal and the first clock signal.

Connecting digital storage oscilloscopes

Circuitry includes a pre-amplifier having a differential output, where the differential output corresponds to a common mode voltage; a multiplexer including sets of transistors, each of which has a control input; a comparator including input terminals, a first terminal of the input terminals to receive a signal that is based on an output of the multiplexer, and a second terminal of the input terminals to receive a threshold voltage; a compensation circuit to produce a divided voltage that varies in accordance with variations in the common mode voltage; and an amplifier to receive a predefined voltage and to use the divided voltage to affect the predefined voltage to produce the threshold voltage for the comparator. Signals in the differential output of the pre-amplifier are applicable to corresponding control inputs in the sets of transistors.

Driving an electronic instrument

Circuitry includes a comparator to compare an input analog signal to a threshold and to output a signal that is based on the comparison; a first circuit path to receive the signal and to detect a characteristic of the signal, where the first circuit path is configured to support triggering at a first frequency; a second circuit path to receive the signal and to detect the characteristic of the signal, where the second circuit path is configured to support triggering at a second frequency that is lower than the first frequency; and a selector to select an output of the first circuit path or an output of the second circuit path.

Multi-level triggering circuit

An attenuator circuit includes a high-frequency circuit path to produce an attenuated first signal; a low-frequency circuit path to produce an attenuated second signal, where the attenuated first signal has a higher frequency than the attenuated second signal; and a transistor that includes a control input. The control input is configured to receive the attenuated second signal to bias the transistor for passage of the attenuated first signal and the attenuated second signal.

Attenuator circuit

A device for providing a precision current includes a first operational amplifier and multiple path transistors. The first operational amplifier outputs a gate voltage based on reference voltage and input voltages. The path transistors have corresponding gates for receiving the gate voltage from the first operational amplifier. Each path transistor is connected to a first enable transistor configured to selectively connect the path transistor to a reference path and a second enable transistor configured to selectively connect the path transistor to an output path. The first and second enable transistors are separately enabled by first and second enable signals, respectively. At least one path transistor is connected to the reference path through a corresponding first enable transistor to provide the reference current, and least one other path transistor is connected to the output path through a corresponding second enable transistor to provide the precision current based on the reference current.

Precision current source

Circuitry and methods for improved amplifiers with large bandwidth and constant gain are provided. The combination of a synthetic inductive drain load and a bridged-T matching network provide amplifiers that can drive a substantial capacitive load with the above mentioned improvements over prior amplifiers. Additionally, circuits presented allow for improved rise time and insensitivity to temperature variations.

Ultra-wideband constant gain CMOS amplifier

Light emitting elements with preselected or adjustable impedance characteristics are provided. Embodiments using a preselected impedance characteristic obtain significant performance benefits compared to the prior art. Embodiments having an adjustable impedance may alter the impedance associated with the light emitting component such that it has a substantially constant resistive or reactive impedance that improves certain performance attributes. This solution virtually eliminates the need for external compensation components and relieves the burden of impedance matching and circuit specialization from the driver circuit.

Circuitry and methods for improving the performance of a light emitting element

Circuitry and methods for obtaining accurate measurements of current supplied by an integrated circuit are provided. Current calculations are performed using information from a precision termination resistor and from the ratio relationship of two on-chip resistors. The invention provides a way to obtain accurate current measurements without the use of component trimming.

Circuits and methods for current measurements referred to a precision impedance

Circuitry and methods for current measurements referred to a precision impedance

Circuits and methods for automatically controlling lightwave emitters are provided. A control system is provided that includes a variable gain circuit for automatically adjusting the gain of a control signal with respect to a feedback signal, a modulation signal, and a reference signal. This allows the optical output of the lightwave emitter to remain substantially constant despite changes in transfer ratio due to aging or temperature variations. Furthermore, in some embodiments, a user may select the overall gain of the system to optimize response time, bandwidth, or steady-state accuracy.

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Colorado Springs, CO, United States of America

Steven Douglas Roach